hardened teeth secured with 10-24
screws. The new blades would be in
the much tougher 7075 aluminum and
have professionally hardened S7 teeth
secured with bigger 12-24 screws.

I designed the new blade
assembly in Solid Works® and used
the “Mass Properties” tool to check
that the weight was the same as the
original Maniac Kathy version.

I like working with aluminum so
I decided to make the blades myself.
I’m not so keen on working with S7
steel, needing multiple teeth per
blade, and with them also requiring
heat treatment, so I sent my
drawings to Team Whyachi
( www.teamwhyachi.com) and
ordered a batch of 10.

A lot of the time spent
machining something like these
blades is in setting up the machines
for each operation. The time to
make four blades is probably only 2X
the time to make a single blade.
With this in mind, I decided to make
a batch of four blades.

Caution: Mills are potentially
very dangerous machines. Do not
wear any rings, a wristwatch, or
jewelry; remove any loose clothing;
tie back long hair; and wear eye
protection at all times!

The first task was to cut four
blanks (Figure 2) out of the 1/2“ x
1-1/2” x 48” 7075 aluminum bar.
Each blade was to be 11” long so
each blank was cut to about 12”